Shape and pressure adjustable dressing

ABSTRACT

A method for applying pressure to skin with a dressing. The method including adhering at least a portion of the dressing to the skin and changing the shape of the dressing after application of the dressing to the skin wherein the changed shape applies pressure to the skin. The changing can include releasing a member from the dressing to allow the dressing to change the shape of the dressing; deforming at least a portion of the dressing to change the shape of the dressing or allowing the dressing to heat to above a transition temperature at which the dressing changes shape.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of provisional application Ser. No.60/872,190 filed on Dec. 2, 2006, the contents of which is incorporatedherein by reference.

BACKGROUND

1. Field of the Invention

The present invention relates generally to dressings, and morespecifically to shape and pressure adjustable dressings.

2. Prior Art

In many situations, dressings are desired to apply a certain amount ofpressure on a wound or to apply a certain amount of force to close awound or keep it closed, even over time as inflammation subsides. Inother situations, it may be desired to increase the pressure or forceover time to assist healing without a change in the dressing. In yetother situations it may be desirable to vary the pressure or forcedistribution over time. However, the currently available materials usedfor dressing wounds are difficult if not impossible to be used toachieve the above results in general, and to achieve it with ease and ina reliable manner in particular, even with the use of such aids aselastic components or tension fixtures.

In other situations, the dressing may be required to cover certainsurfaces over the body that due to the shape of the surfaces, it may bedifficult to make a close fit and even more difficult to apply pressureto the surface and sustain the applied pressure over time. In suchsituations, the dressing has to not only conform to the coveredsurfaces, but at the same time may have to provide a certain pattern ofpressure or force to achieve certain goals.

A need therefore exists for a method to construct dressings that can bereadily applied to the desired area, and then have the capability of itsshape to be varied and/or apply a desired pattern of pressure or forceto the covered area. The disclosed methods of varying the shape of thecomponent just before use, is also advantageous in many applicationssince it can be used to reduce the size of the required packaging, e.g.,a blister shaped component may be initially stored as a relatively flatsheet and then be turned to a blister just before application to thepatient's skin.

SUMMARY

It is an object of the present invention to provide methods and/ordressings that: a) can be readily applied to a desired area, includingareas that are hard to cover due to their shape and geometry; b) can bemanipulated to change its shape in a predetermined manner (before orafter its application); c) can be made to apply pressure (or a pullingforce) to the covered area; and/or d) can be made to apply a force, forexample an opening or closing force, in certain direction to the coveredarea.

Accordingly, a dressing for covering a wound is provided. The dressingcomprising: a first component having a first shape; a second componentreleasably attached to the first component to maintain the firstcomponent in a second shape different from the first shape; and meansfor attaching a surface of the first shape to the wound such that thesecond component can be released from the first component to allow thefirst component to take the first shape to apply a pressure to portionsof the skin surrounding the wound.

The second shape can be flat. The first shape can be curved in at leasta portion of the first component.

The means for attaching the surface of the first shape to the wound canbe an adhesive.

The first component can further comprise one of a medicament and gauze.

The first component can include discontinuities in the first shape andsuch discontinuities can be living joints.

Also provided is a dressing for covering a wound. The dressingcomprising: a component having a first shape and a surface for contactwith the skin of a patient; means for attaching the surface to the skinof the patient; and means for changing the first shape to a second shapeafter attachment of the surface to the skin to apply a pressure to theskin.

The means for attaching the surface to the skin of the patient cancomprise an adhesive.

The means for changing the first shape to a second shape can comprisethe component having a portion not in contact with the skin which can bedeformed to likewise deform the component into the second shape.

The means for changing the first shape to a second shape can comprisethe component at least in part being formed of a shape memory materialwherein a change in temperature of the component due to contact with theskin causes the component to take the second shape.

The first component can further comprise one of a medicament and gauze.

Still yet provided is a butterfly for closing a wound of a patient. Thebutterfly comprising: a butterfly body having a narrowed portion and twowider end portions, at least a portion of the narrowed portion beingformed of a shape memory material; and an adhesive for applying at leastthe two wider portions to skin surrounding the wound; wherein the shapememory material of the butterfly body having a first shape below atransition temperature and a second shape above the transitiontemperature, where the transition temperature is substantially equal toa body temperature of the patient.

The first shape can be flat. The second shape can be curved in at leastthe narrowed portion.

The first component can further comprise one of a medicament and gauzedisposed on a surface corresponding to the narrowed portion.

Still yet further provided is a method for applying pressure to skinwith a dressing. The method comprising: adhering at least a portion ofthe dressing to the skin; and changing the shape of the dressing afterapplication of the dressing to the skin wherein the changed shapeapplies pressure to the skin.

The changing can comprise releasing a member from the dressing to allowthe dressing to change the shape of the dressing.

The changing can comprise deforming at least a portion of the dressingto change the shape of the dressing.

The changing can comprise allowing the dressing to heat to above atransition temperature at which the dressing changes shape.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the apparatus andmethods of the present invention will become better understood withregard to the following description, appended claims, and accompanyingdrawings where:

FIG. 1( a) illustrates a first embodiment of a dressing having a firstlayer and a second layer.

FIG. 1( b) illustrates the dressing of FIG. 1( a) in which the first andsecond layers are separated.

FIG. 1( c) illustrates the first layer of FIG. 1( b) after the secondlayer has been separated therefrom.

FIG. 2( a) illustrates the dressing of FIG. 1( a) attached to thesurface of skin.

FIG. 2( b) illustrates the dressing of FIG. 2( a) after the second layerhas been removed.

FIG. 3( a) illustrates two component sheets of a second embodiment of adressing.

FIG. 3( b) illustrates the two component sheets of FIG. 3( a) attachedinto an assembly.

FIG. 3( c) illustrates one of the components of FIG. 3( b) attached tothe skin of a patient and the other of the components separatedtherefrom.

FIG. 4( a) illustrates another embodiment of a dressing.

FIG. 4( b) illustrates the dressing of FIG. 4( a) attached to skin of apatient.

FIG. 4( c) illustrates the dressing of FIG. 4( b) being compressedtogether.

FIG. 5( a) illustrates a top view of yet anther embodiment of adressing.

FIG. 5( b) illustrates a side view of the dressing of FIG. 5( a) when ata temperature lower than a threshold temperature.

FIG. 5( c) illustrates the dressing of FIGS. 5( a) and 5(b) attachedover a cut in skin.

FIG. 5( d) illustrates the dressing of FIG. 5( c) after the dressing hasattained a temperature greater than the threshold temperature to closethe cut in the skin.

DETAILED DESCRIPTION

A schematic of a basic design based on a first embodiment is shown inthe FIG. 1( a) to 1(c). In FIG. 1( a), the cross-section of a planeassembly 100 is shown, and consists of a first layer 101 and a secondlayer 107. The two layers are attached together using any methods knownin the art, such as with adhesives, so that the user could readilyseparate them. The layer 101 consists of components 102 and 104, whichare attached together with an intermediate component 103. Similarly, thecomponents 104 and 106 are attached together with an intermediatecomponent 105. The components 102, 104 and 106 are considered to berelatively devoid of internal stresses, while the components 103 and 105have been originally shaped as shown in FIG. 1( c), but have beenelastically flattened and held in the flattened configuration by thecomponent 107, as shown in FIG. 1 a, to form the assembly 100.Obviously, if the component (layer) 107 is separated from the assembly100, as shown in FIG. 1( b), the components 103 and 105 would return totheir original shape, and the layer 100 will take the shape shown inFIG. 1( c).

The first layer 101 can be formed of any material which can befabricated into a certain (original) shape and elastically deformed intoanother shape, such as a plastic or metal or combination thereof.Furthermore, plate 107 can be formed of any material rigid enough toprevent the first layer 101 from taking the original shape whileattached to the first layer.

In the schematic of FIGS. 1( a)-1(c), the assembly 100 is shown to be inthe shape of a flat plate. It is, however, appreciated by those skilledin the art, that the assembly may form a curved surface; more stressed(preloaded or elastically deformed) and essentially unstressed(preloaded or elastically deformed) components may be used in theassembly; and in their unstressed state, the stressed (preloaded orelastically deformed) component(s) may have been constructed to assume avariety of shapes (configurations), including complex shapes andcurvatures. In general, upon the removal of the constrainingcomponent(s), the stressed (preloaded or elastically deformed)component(s) will tend to return to their unstressed (natural) state. Itis appreciated that the stressed component(s), while tending to returnto their unstressed (natural) state (shape or configuration), may stillretain part of their induced internal stresses.

The dressing assembly 100 may be applied to the body surface 110, e.g.,via an adhesive layer on the free surface of the layer 101 (not shown),as can be seen in FIG. 2( a). Once the assembly 100 is securely attachedto the body surface, the layer 107 (wholly or partially) is removed.FIG. 2( b) shows the case in which the layer 107 is removed. At leastpart of the preloading stresses in the components 103 and 105 are thenreleased. As a result, the layer 101 tends to its natural (stress-free)state. The components 102 and 106 are then pulled towards each other inthe direction 112, and the underlying skin is pulled together. Therebyif a cut was present in the section of the skin 111 between the 102 and106 components, the above action would tend to force it closed. Thecomponent 104 of the layer 107 is also pushed away from the skin.

In the schematics of FIGS. 1( a)-1(c), for the sake of simplicity, onlytwo distinct layers are used and only one of the layers is provided withthe preloaded components. However, more than one layer can be utilized,and layers with partially preloaded components may also be used toconstruct the dressing components. It is also possible to constructdevices that are constructed with at least two layers of fully preloadedcomponents. In addition, the final assembly (assembly 100) does not haveto be flat, and may assume any appropriate shape and configuration asdictated with the particular application.

It should also be noted that in the schematics of FIGS. 1( a)-1(c), andin the remaining illustrations, only living joints are illustrated atdiscontinuities in the first layer 101. It is, however, appreciated thatregular joints, such as pin joints and/or sliding joints, may also beused in the construction of the present devices.

Another embodiment of a dressing is shown schematically in FIGS. 3(a)-3(c). The dressing assembly 200 shown in FIG. 3( b), consists of atleast two components (sheets) 201 and 202, which in their free (natural)form are curved as shown in FIG. 3( a). The dressing 200 is assembled bydeforming the components 201 and 202 to their assembly configuration andattaching them together, preferably using adhesives, to achieve theirfinal (assembled) configuration. In FIG. 3( a), and for the sake ofsimplicity, the two components 201 and 202 are shown to be deformed in asymmetrical manner, which upon bending in the directions 203 and 204,respectively, could be nearly flattened to their final shape in theassembly. In this particular case, since the two components 201 and 202are considered to be identical and with symmetrical initial deformation,then upon their assembly after being flattened would assume a flatconfiguration. It is readily seen that by using two or more componentswith varying shape, and/or size, and/or materials, and/or initial (freeor natural) configuration, one could construct infinite number ofassemblies, which upon partial or full removal of one or more of thecomponents, the desired final shape, size, configuration, and whenappropriate applied force (moment or torque) to the attached member,could be achieved.

In certain assemblies, it may be necessary to use less strong adhesivesfor assembling certain components of the assembly for reasons such asease of removal. In such cases, it may be necessary to providemechanical locking action, such as by bending sides or corners of onecomponent over the other, or by using attachment methods such as sewingor stapling or by using one or more clipping elements, etc., whichis/are readily removable before applying the dressing to the patient orfollowing its application. FIG. 3( c) illustrates the dressing 200attached to a surface of the skin and sheet 202 removed, in which casesheet 201 is deformed towards its original shape and the skin takes theshape of the sheet 201 and is pulled together.

Yet another embodiment of a dressing is shown in FIGS. 4( a)-4(c). Theschematic of the side view of a plate formed with two flat sides 231 anda middle side 232, forming a simple example of a dressing element 230 isshown in FIG. 4( a). The adhesives that are preferably provided on thesesurfaces may then apply the dressing element 230 to the surface of theskin 233 as shown in FIG. 4( b), via the surfaces 231. The part 232 isthen compressed together (or twisted or otherwise deformed) in thedirection of bringing the surfaces 231 together (direction 235), such aswith a tie-wrap, string wire or the like. As a result, the underlyingskin is pulled together in the direction 234, thereby closing a wound orproviding a desired compressive pressure, or in short the desiredeffect.

In all the disclosed embodiments, appropriate dressing components suchas gauzes, medications, etc., may be disposed (preferably in the middleregions) of the dressing assemblies to cover the wound. Ventilation ordrainage ports may also be provided when appropriate in these regions.Elastic or removable elements may also be provided over or around suchregions for administering medication. In certain cases, it may also bedesirable to construct one or more components of the assembly withtransparent materials so that the affected region could be observed.

In addition, in all the disclosed embodiments, the applied pressure orwould closing action of the dressing element may be increased ordecreased over time by removing, e.g., a larger piece of theshape/configuration affecting components or by further deformation ofthe shape/configuration affecting components. You can also vary thepressure applied by the dressing so that the skin can be “pushed” and“pulled.”

Referring now to FIGS. 5( a)-5(d), the component 101, 201 disposed onthe skin can be formed, at least in part, of a shape memory material.Thus, when disposed on the skin, the component 101, 201 can changeshape, in whole or in part, due to a shape memory effect upon beingheated by the temperature of the skin to at or above a transitiontemperature of the shape memory material. Such materials are well knownin the art and can be either metals or plastics which exhibit the shapememory effect. A dressing having such a configuration can eliminate thesecond component 107, 202 since the shape memory material can take oneform, such as flat, at a first temperature (FIG. 5( b)) and take anothershape, such as that shown in FIG. 5( d) at a second temperature. Thus,the plate 107, 202 is not needed to maintain the sheet 101, 201 in theshape shown in FIGS. 5( a) and 5(b). In this configuration, the dressingcomponent can be shaped as shown in FIG. 5( d) when subjected to atemperature above the threshold temperature (e.g., body temperature) andcan be flat when subjected to a temperature lower than the thresholdtemperature.

This dressing has particular utility when used as a butterfly typedressing for closing wounds that may otherwise require stitches. In thisregard, the plan or top view shape of the dressing 101, 201 can beshaped like a conventional butterfly bandage having a narrowed sectionin the middle thereof, as shown in FIG. 5( a). Once placed over a cut300 on the skin 302, such as with adhesive on a face 303 of the dressing101, 201, as shown in FIG. 5( c), preferably disposed on the surfaceoutside of the narrowed portion. After the dressing 101, 201 is warmedby the body heat of the skin, the shape memory material changes itsshape to another shape, such as that shown in FIG. 5( d) to close thecut 300 by applying pressure in the direction of arrows 304. The portionof the dressing 101, 201 contacting the cut 300 may have a gauze and/ora medicated layer.

In a variation of such embodiment, the shape memory material dressingcan be kept cool and applied to the skin while it is cold. Then the roomtemperature will activate it to change its shape so that you are notlimited to activation with body temperature, which might be very closeto the environmental temperature.

Other active materials that could be employed for the dressing could beactive polymers, which would require a voltage to get them to pull.

While there has been shown and described what is considered to bepreferred embodiments of the invention, it will, of course, beunderstood that various modifications and changes in form or detailcould readily be made without departing from the spirit of theinvention. It is therefore intended that the invention be not limited tothe exact forms described and illustrated, but should be constructed tocover all modifications that may fall within the scope of the appendedclaims.

1. A dressing for covering a wound, the dressing comprising: a firstcomponent having a first shape; a second component releasably attachedto the first component to maintain the first component in a second shapedifferent from the first shape; and means for attaching a surface of thefirst shape to the wound such that the second component can be releasedfrom the first component to allow the first component to take the firstshape to apply a pressure to portions of the skin surrounding the wound.2. The dressing of claim 1, wherein the second shape is flat.
 3. Thedressing of claim 1, wherein the first shape is curved in at least aportion of the first component.
 4. The dressing of claim 1, wherein themeans for attaching the surface of the first shape to the wound is anadhesive.
 5. The dressing of claim 1, wherein the first componentfurther comprises one of a medicament and gauze.
 6. The dressing ofclaim 1, wherein the first component includes discontinuities in thefirst shape and such discontinuities are living joints.
 7. A dressingfor covering a wound, the dressing comprising: a component having afirst shape and a surface for contact with the skin of a patient; meansfor attaching the surface to the skin of the patient; and means forchanging the first shape to a second shape after attachment of thesurface to the skin to apply a pressure to the skin.
 8. The dressing ofclaim 7, wherein the means for attaching the surface to the skin of thepatient comprises an adhesive.
 9. The dressing of claim 7, wherein themeans for changing the first shape to a second shape comprises thecomponent having a portion not in contact with the skin which can bedeformed to likewise deform the component into the second shape.
 10. Thedressing of claim 7, wherein the means for changing the first shape to asecond shape comprises the component at least in part being formed of ashape memory material wherein a change in temperature of the componentdue to contact with the skin causes the component to take the secondshape.
 11. The dressing of claim 7, wherein the first component furthercomprises one of a medicament and gauze.
 12. A butterfly for closing awound of a patient, the butterfly comprising: a butterfly body having anarrowed portion and two wider end portions, at least a portion of thenarrowed portion being formed of a shape memory material; and anadhesive for applying at least the two wider portions to skinsurrounding the wound; wherein the shape memory material of thebutterfly body having a first shape below a transition temperature and asecond shape above the transition temperature, where the transitiontemperature is substantially equal to a body temperature of the patient.13. The butterfly of claim 12, wherein the first shape is flat.
 14. Thebutterfly of claim 12, wherein the second shape is curved in at leastthe narrowed portion.
 15. The butterfly of claim 12, wherein the firstcomponent further comprises one of a medicament and gauze disposed on asurface corresponding to the narrowed portion.
 16. A method for applyingpressure to skin with a dressing, the method comprising: adhering atleast a portion of the dressing to the skin; and changing the shape ofthe dressing after application of the dressing to the skin wherein thechanged shape applies pressure to the skin.
 17. The method of claim 16,wherein the changing comprises releasing a member from the dressing toallow the dressing to change the shape of the dressing.
 18. The methodof claim 16, wherein the changing comprises deforming at least a portionof the dressing to change the shape of the dressing.
 19. The method ofclaim 16, wherein the changing comprises allowing the dressing to heatto above a transition temperature at which the dressing changes shape.